/**
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.datayoo.moql.operand.expression;

import org.apache.commons.lang3.Validate;
import org.datayoo.moql.EntityMap;
import org.datayoo.moql.Operand;
import org.datayoo.moql.SelectorConstants;

import java.util.List;

/**
 * @author Tang Tadin
 */
public class OperandsExpression extends AbstractExpression {
	
	protected List<Operand> operands;
	
	public OperandsExpression(List<Operand> operands) {
		Validate.notEmpty(operands, "operands is empty!");
		
		this.operands = operands;
		expressionType = ExpressionType.OPERANDS;
		name = buildNameString();
	}
	
	protected String buildNameString() {
		StringBuffer sbuf = new StringBuffer();
		sbuf.append(SelectorConstants.LPAREN);
		int i = 0;
		for(Operand operand : operands) {
			if (i++ != 0)
				sbuf.append(SelectorConstants.COMMA);
			sbuf.append(operand.toString());
		}
		sbuf.append(SelectorConstants.RPAREN);
		return sbuf.toString();
	}
	
	@Override
	public Object operate(EntityMap entityMap) {
		// TODO Auto-generated method stub
		return operands;
	}

	public List<Operand> getOperands() {
		return operands;
	}
}
